Concrete mattress leveling and finishing machine having reciprocating screeds



July 17, 1956 A. BEYER ,75

CONCRETE MATTRESS LEVELING AND FINISHING MACHINE HAVING RECIPROCATINGSCREEDS Filed Feb. 27, 1952 :5 Sheets-Sheet 1 INVENTOR. ARNOLD BEYERJuly 17, 1956 A. BEYER 2,754,732

CONCRETE MATTRESS LEVELING AND FINISHING MACHINE HAVING RECIPROCATINGSCREEDS Filed Feb. 27, 1952 3 Sheets-Sheet 2 M 0W? 3 y INVENTOR.

NOLD BEYER A. BEYER July CONCRETE MATTRESS LEVELING AND FINISHINGMACHINE HAVING RECIPROCATING SCREEDS 3 Sheets-Sheet 3 Filed Feb. 27,1952 m FIG. 7.

A96 A27 A a/a e 434 /2 he A86 //Z W m W /76 my ARNOLD OR.

erras United States Patent '0 CONCRETE'MATTRESS LEVELING AND FINISH- ING'MACHINE HAVING RECIPROCATING SCREEDS Arnold Beyer, Memphis, Tenn.,assignor to Weymouth Construction Company, Memphis, Tenn., 2 corporationof Wisconsin ApplicationFebruary 27, 1952, Serial No. 273,591

4 Claims. (Cl. 94-1-45.)

This invention appertainsto improvements in machines for leveling andfinishing largeconcrete areas, such as floors, platforms and roadwaysand more particularly to an improved concrete finishing machine,designed for use in connection with the constructionof articulatedconcrete mattresses.

Such concrete mattresses are constructed in accordance with UnitedStates Army specificationsand are approximately four feet wide,twenty-five feet long and three inches'in thickness. The methodofconstruction consists of casting approximately five hundred .to sevenhundred squares of mattress on the ground and then casting additionalmattresses, one on top of each other, each layer of mattress beingseparatedby two thicknesses of kraft paper until the mattresses are cast.in stacks twelve high or over thirty-six inchesin overall height.

The primary object of this invention is to .:level and finish the topsurface of the concrete mattress and,.therefore, one of the importantfeatureslof the invention resides in the provision of a screed, which isadjustable from a height of approximately three inchesto thirty-sixinches from the ground.

Another object of this invention is to provide a pair of side by side,rectilinearly out-ofephase reciprocating screeds, which are mounted on avertically adjustable frame that is supported by a mobile carriagedesigned to straddle the mattresses and move longitudinally thereof soas to carry the screeds longitudinally over :the mattresses as theyreciprocate transverse to the path of movement of the carriage.

A further object of this invention is to provide a screed having aresilient belting and wherein the pressure exerted against the plasticconcrete is transmitted by ,the tautness of the resilient belting, whichdirectly engages the surfaceof the mattress and produces-a denseconcrete with a uniform finish. The belting is supported in a tautcondition by an open arched frame that is reciprocated over the surfaceof the mattress.

A still further object of this invention is to provide -a pair ofcooperating screeds, which are supported by a vertically adjustableframe in side by side relation and which are reciprocated inout-of-phase relation and in parallel rectilinear paths of movement byaprime mover, mounted on the supporting frame.

These and ancillary objects and structural features of merit areattained by this invention, the preferred embodiment of which is setforth in the following description and illustrated in the accompanyingdrawings, wherein:

, Fig. 1 is a perspective view of the concrete surface finishing andleveling machine;

Fig. 2 is a view in perspective of the vertically adjustable supportingframe and companion screeds;

:Fig. 3 is a view in perspective of one of the screeds;

Fig. 4is a transversesectional view taken on line 44 of Fig. 3;

Fig. 5 is a transverse sectional view taken on line 5-5 o sice "Fig. 6is an enlarged detailed sectional .view taken on line 6- 6 of Fig.5;

"Fig. 7 is a top plan view of the supporting frame and screeds;

Fig. 8 is a fragmentary sectional view taken on line 8-8 of-Fig. 7, and,

Fig. '9is a View, partially in-section, of the shaft and drums forvertically adjusting the supportingframe.

Referring now more particularly to the accompanying drawingsandinitially to Fig. 1 thereof, the concrete mattressfinisher 10includes a mobile carriage 12, which has an open rectilinear main frame:14 on which a conventional internal combustion engine (not shown) ismounted. The engine 'is conventionally supported within a housing -16,which is mounted bybrackets '18 on the frame. An operators seat 20-ismounted by means of brackets 22 on the frame rearwardly of the enginehousing and an axle2 i is rotatably supported'by the vertical sectionsof the brackets, so that the .ends extend outwardly of and above theopposing sides of the frame 14. Theaxle is rotated by the engine througha conventional transmission and differential.

Tubular legs '25 and 28am secured at their upper ends to-the opposingsides of the frame 14 adjacent the :front end thereof and carrysteerable, ground engaging wheels '30 and ZZ-at their lower ends. Thewheels '30and 32 are equipped'withstandard pneumatic tires and thesteering is accomplished'by a standard type steering gear 34.

Standards 38 are mountedat their upper ends to the sides of the frame 14adjacent the rear end thereof'and are rigidificd-bya transverse brace 46and by bracing 42, The lower bifurcated ends 44 0f the standards ro'-tatably support ground engaging wheels .46, which are driven from theaxle 24 by a chain drive 48. The chain 48 isentrained over a sprocket50fixed on the extending ends of the axle 24 and overa sprocket (notshown) which is fixedly 'circumposed on the wheel axles '51. A chaintightening-sprocket 52 is carried by an arm 54 that extends forwardlyfrom the inner branch of'the lower'bifurcated ends of the standards, theforward reach of the chain being entrainedunder and held tight 'by theidler sprocket 52.

The frame 14 is of a width slightly larger than the width of theconcrete mattress, .that is, a width slightly inexcess of 'four'feet, sothat rear standards 38 and the front tubular legs 26 and 28 straddle themattress with the frame horizontally overlying and overlapping themattress. The carriage is propelled'bythe driven wheels 46longitudinally over the mattresses.

To effectively position the carriage and avoid damage to the sides of.the mattress, which is in a slightly plastic state, guide means or,guards are'provided and preferably include plates 56, which areelongated and transversely curved. The plates are aflixed at theirconcave faces 'to the inner surfaces of the tubular legs and standardsand are disposed at the lower ends of the legs and standards in a mannerto encompass the inner portions thereof. The plates are slightly curvedaround the legs and standards so as :to prevent the 'legs and standardsfrom contactingthe opposing sides of the mattress. The plates have theircurvedsurfaces confronting and engaging the sides of the mattress andthe sides will, therefore, not be subjected toany-piercing or gougingforce. Additionally, the plates will act as guides for .thecarriage.

.A vertically adjustable supporting frame 58 is carried by the carriage12 and suspended from the frame -14, inwardly of the ends and sidesthereof. The frame 58 :is .of rectangular shape and includes opposingchannel shaped sides 60 and 62, having their open sides in confrontingrelation. The side channels are weldedor otherwise-secured .at theirends to end channels 64 and :66. The

corners of the frame are rigidified by triangular plates 68, which arewelded or otherwise fixedly superimposed on the top of the frame at thecorners.

Tubular standards or pipes are afiixed at their lower ends to the plates68 and, thus, project upwardly from the four corners of the supportingframe 58 for engagement with the cross bars 72 and 74, which extendbetween the sides of the frame 14. The cross bars 72 and 74 are formedwith vertical openings adjacent the sides of the frame 14. Collars 0rrings 76 are fitted in the openings to reinforce the walls thereof andthe collars slidably receive the tubular standards or pipes 70.

Means is provided for raising and lowering the frame 58 by sliding thetubular standards upwardly and downwardly through the collars 76 in thecross bars. The means, shown in Figs. 1 and 9, is manually operated butpower means may be provided for effecting the vertical adjustment of theframe 58. The means includes a shaft 78, which is rotatably supported bybrackets 80 and 82, that are mounted on the opposing sides of the frame14, so that the shaft underlies the housing 16. Double drums 84 and 86are fixedly circumposed on the shaft and located on the ends thereofagainst movement axially of the shaft by stop collars 88.

On each of the plates 68, a sheave or pulley 90 is mounted, with the web92 of the supporting bracket for the sheave being welded on the platesinwardly of the tubular standards 70. Cables 94 are fixed at one oftheir ends by nuts 96 to the cross bars, inwardly of the collars 76, andare entrained around the pulley 90 and around guide pulleys 98 carriedby the sides of the frame 14. The opposing ends of the cables aresuitably fixed to the drums.

As seen in Fig. 1, the cable 94 for the left rear end of the frame 58extends under the drum 84a, while the cable 94' for frame 58 extendsover the drum 84b. A similar arrangement is provided for the cables 94,that support the other corners of the frame 58, so that the shaft 78,when rotated by the crank handle 100 in a clockwise direction will windall of the cables on the drums and correspondingly raise or lift theframe 58. counterclockwise rotation of the crank handle 100 will, ofcourse, unwind the cables from their respective drums. A spring urgedpawl and ratchet 102, as seen in Fig. 9, is provided to lock the shaft78 against accidental rotation and prevent accidental unwinding of thecables and consequent dropping of the frame 58.

Companion screeds 104 and 106, of identical construction, are carried bythe frame 58 in a suspended fashion and are reciprocated in out-of-phaserelation and transversely of the path of movement of the carriage, asthe carriage is moved over the mattress, to produce a rough texturefinish, which is level and entirely free from humps or valleys.

The screed 104, as seen in Figs. 3-6, includes an arched rectangularframe 108 having opposing sides 110 and 112. The sides are formed withflat center sections 114, and declined end sections 116 and 118. The endsections 118 of each side of the frame are connected by an integral endbar 120, which is arranged transverse thereto.

The other end of the frame is open and is provided with a cross bar 122,which has a pair of rearwardly directed and longitudinally spaced arms124 and 126. The arms are apertured to receive a rod 128 that extendstransversely between the free ends of the declined end sections 116 ofeach side of the frame. The rod is formed with integral stops 127 thatlocate the arms thereon.

The declined end sections 116 of each of the sides 110 and 112 of theframe are formed with upstanding apertured ears 130 and 132 that arearranged in confronting relation to upstanding ears 134 and 136 formedvertically on the ends of the end bar 122. Elongated bolts 138 aredisposed through the apertures in the confronting ears 130 and 136 andthe ears 132 and 134 to adjustably fix 4 the end of the frame to the endbar 122, for a purpose to be described.

An elongated rectangular shaped resilient belting 140 is carried by theends of the frame and is secured thereto in taut condition. One end ofthe belting is secured to the end bar 120 of the frame by a clampingplate 142, which is secured by bolts 144 to the end bar 120, with theend of the belting clamped between the plate and the end bar. The otherend of the belting is secured to the end bar 122 by a similar clampingplate 146 and bolts 148, that pass through the plate and belting. Thebolts 138 are provided to take up any slack in the belting, since as thebolts are drawn up tighter, the end bar 122 can swing upwardly about therod 128 to thereby tighten the belting 140.

A flat reinforcing plate 150 is superimposed on the upper surface of thebelting 140 and is preferably of sheet metal or the like material. Asseen in Fig. 5, the plate 150 is formed on its outer side edge with anangular upstanding fiange 152 and the outer side edge 154 of the beltingis turned up and secured by bolts 156 to the flange. The bolts 156constitute the sole fastening means for securing the reinforcing sheet150 on the resilient belting so that the rest of the sheet merely lieson the belting and serves to weight the belting.

The screed 106 is constructed in a manner similar to the construction ofthe screed 104, except that, as seen in Fig. 7, the reinforcing sheet158 is attached to the end bar 122' by a chain or similar connectingmember 160, that is secured to the end of the sheet and to the centerbolt assembly 156. Similarly, the other end of the sheet is secured by achain to the bolt 144'. Thus, the sides and ends of the sheet 158 arenot attached to the resilient belting but are attached to the ends ofthe frame, so that the sheet 158 rests on the upper surface of theresilient belting 140', without any attachment to the belting.

As seen in Fig. 7, the inner side edge of the belting 140 on the screed104 is overlapped by the inner side edge of the belting 140 on thescreed 106, so that the inner side edge of the belting 140' rides overthe adjacent side edge of the belting 140, as the screeds arereciprocated in opposite directions. The inner side edges of thereinforcing plates or sheets 150 or 158 are spaced from the inner sideedges of the respective beltings, so that the inner side edges of thebelting are not reinforced and are unattached.

As seen in Figs. 2 and 8, guide means is provided for each of thescreeds. The guide means includes a pair of vertically arranged plates162 and 164, which are arranged in pairs between the opposing sides 60and 62 of the frame 58. As seen in Fig. 8, the inner confronting facesof the plates are formed with vertically spaced bars and 172 that extendlaterally from each plate and form tracks within which the opposing sideedges of the plate 174 are slidably disposed. The plate 174 is mountedon the ends of the upstanding legs of a channel bar 176, which issupported by a pair of cross bars 178 and 180. The cross bars aretransversely mounted between the center sections 112 on each side of thescreed frames.

Upstanding complementary apertured ears 182 are formed on the uppersurface of the plate 174 for the screed 106 and a similar pair of ears184 are formed on the upper surface of the plate 174' for the screed104. A connecting rod 186 is secured by a wrist pin 188 to the ears 182and connects the plate 174 to the throw 190 of a crank shaft 192. Aconnecting rod 194 is fixed to the ears 184 by pin 196 and connects theplate 174' to the throw 198 of the crank shaft. The ends of the crankshaft are journaled in the bearing blocks 200, which are mounted oncross bars 202 that extend between the sides 60 and 62 of the frame 58.Intermediate the ends thereof, the shaft is supported by hearingbrackets 204, which extend upwardly from the plates 162 and 164.

A sprocket 206 is fixed on one end of the crank shaft and is connectedby a suitable belt and chain transmission W a c nventional gasolineengine 208, which is mounted on one end of the frame 58. The chain 206is driven by the engine through a belt drive 210 and gear reduction unit212, which drives a sprocket 214. The sprockets 206 and 214 areconnected by a chain 216, which is provided with a chain tighteningsprocket 218, that is mounted on a vertically slotted bracket 220, sothat the sprocket 218 can be adjusted vertically with respect to theupper reach of the chain on which it engages.

In operation, the carriage is guided by an operator through the mediumof the front steerable wheels 30 and 32 from the seat 20 and ispropelled by the engine driven axle 24 and chain drive therefrom to therear driven wheels 46. The front tubular legs 26 and 28 and the rearstandards 38 are spaced apart to straddle a row of mattress, so that theframe 12 horizontally overlies the mattress.

Conventionally, approximately 500 to 700 squares of mattress are cast onthe ground, in rows of various lengths. The carriage straddles the rowsand moves longitudinally over the mattress, which are in plastic state.

Each mattress has a width of 4 feet, a length of 25 feet and a depth of3 inches. The mattresses after curing are subsequently shipped topredetermined destinations for use for example by the Air Force forreinforcement installation of emergency landing strips. The mattressesare placed upon sandy or soft ground and a landing strip or mat isplaced thereover.

The gasoline engine 208 is connected to the belt drive 210 by a clutch(not shown) actuated by a clutch handle 222. Before the operator assumeshis position on the seat 20 and operates the carriage in a mannersimilar to the operation of a tractor or other vehicle, the clutch isengaged through the medium of a handle 222 so that the screed frames arereciprocated by the engine 208.

It will be noted that the engine 208 is disposed at the front end 66 ofthe frame 58 so that the front of the carriage is weighted in order tocounteract the weight of the engine and operator at the rear of theframe 12. The frame 58 is adjusted by using the crank 100 and throughthe medium of the pulleys and cable system, so that the under surfacesof the beltings 140 and 140' are in direct engagement or contact withthe upper surfaces of the freshly poured concrete mattress, as thecarriage is driven longitudinally over the mattress. The screeds arereciprocated transversely of the path of movement of the carriage ortransversely of the longitudinal axis of the mattress in a sawing actionor out-of-phase rectilinear paths of movement. The flange 152 and outerside edge 154 of the belting 140 form the lead edge, as the carriage isdriven over the mattress. Thus, as seen in Fig. 1, the lead edge of thefirst screed 104 is upturned so that it rides over and smooths down theplastic concrete forming the upper surface of the engaged mattress. Thisprevents any gouging of the surface.

The first screed 104 has its reinforcing plate 150 secured to the leadedge 154 thereof, so that the reinforcing plate weights the lead edgeand rests on the belting in a somewhat overall secured manner.

The belting 140 on the lead or first screed 104 is therefore weightedmore than the belting 140 on the trailing or second screed 106. Thereinforcing plate or sheet 158 on the belting 140 of the trailing screed106 floats on the belting, since it is not secured to the belting but issecured at its ends to the ends of the frame for the trailing screed106.

Thus, the lead screed 104 packs down, due to its weight, the surface ofthe mattress, as it is moved longitudinally over the surface andreciprocated transversely thereof. The belting 140' on the trailingscreed is held in taut condition and the reinforcing plate floatsthereon so that the pressure that the belting 140' exerts against thefresh concrete is transmitted by the tautness of the rubber belting andnot through any direct pressure by the reinforcing plate on any of theparts of the frame which support the belting.

The reciprocating screeds, by the rectilinear or sawing and screedingaction, produce final consolidation of the concrete and the finalfinishing. The end result is a dense concrete, packed by the lead screed104 and initially smoothed thereby and finally smoothed or leveled bythe trailing screed 106. The finish is a rough texture, rather than asmooth or glassy finish, and is perfect in alignment and entirely freeof humps or valleys.

After the first row of mattress has been finished, a double layer ofkraft paper is laid on the finished upper surface and an additionalmattress is cast on top of the kraft paper. The frame 58 is then raiseda distance of approximately three inches, so that the engaging or undersurfaces of the belting and 140' are positioned for direct and propercontact with the plastic upper surface of the freshly poured secondlayer of concrete mattress.

The operation is continued, with the frame 58 being raised, asadditional layers of mattress are cast, until the mattresses are cast inlayers or stacks approximately twelve high.

While a specific form of drive means for the carriage and specific typeof prime mover and operating means for the screed frames has been shownin the disclosed and preferred embodiment, it is understood that changescan be made in these details, as well as in other parts of the disclosedembodiment, so that limitation is sought only in accordance with theappended claims.

Having thus described this invention, what is claimed 1s:

1. A machine for the finishing of concrete mattresses laid in successivevertical tiers comprising a rectangular mobile frame, vertical legssupporting the four corners of the mobile frame, wheels supporting saidlegs, means for driving at least two of said wheels for propelling saidmobile frame at a uniform rate of speed over the tiers of mattresses, asupport sub-frame adjustably supported below said mobile frame, a pairof transverse screed mem' bers carried by said support frame, means forreciprocating said screed members in opposed directions, means toelevate said sub-frame for vertical adjustment whereby the screeds canbe reciprocated at seelcted levels whereby successive vertical tiers ofmattresses can be finished as the machine is passed longitudinallythereover.

2. A machine for successively finishing concrete mattresses individuallyas the mattresses are laid in vertical stacks as claimed in claim 1wherein said elevating means for said support means comprises hoistmeans carried by said mobile frame one element of which is connected tosaid support means for raising and lowering said support means withinsaid mobile frame.

3. A machine for successively finishing concrete mattresses individuallyas the mattresses are laid in vertical stacks as claimed in claim 2further comprising guide means one end of which is carried by saidsupport means and the other end of which passes through a portion ofsaid mobile frame for guiding said support and its reciiprocatingscreeds for varying positions of said screeds as the stack of mattressesbecomes successively higher.

4. A machine for successively finishing concrete mattresses individuallyas the mattresses are laid in vertical stacks as claimed in claim 1wherein said support means comprises a vertically movable platformsupporting thereon drive means for reciprocating said screeds carried bysaid platform.

References Cited in the file of this patent UNITED STATES PATENTS1,271,947 Ross July 9, 1918 1,832,951 Thorson Nov. 24, 1931 1,978,773Trant Oct. 30, 1934 2,054,263 McCrery Sept. 15, 1936 2,192,027 CrowderFeb. 27, 1940 2,529,749 Wade et al. Nov. 14, 1950 OTHER REFERENCESEngineering News Record, Oct. 9, 1919, page 712.

